The <img src="spyder.gif" width=15 height=15 align=middle border=0>hole is hands down the best mix of easy and fast in a folder. The Emerson wave, I've heard, can be faster, and some with the large textured, bezeled thumb studs can be easier (I've seen a lot of Delica knockoffs with large thumbpads like this), but the Spyderhole is simple, fast, easy to use, and easy to maintain (just swab it out with a cotton rag and some polish once in a while to get rid of any rust).
One of the best ideas I've heard to improve the <img src="spyder.gif" width=15 height=15 align=middle border=0>hole would be to have an available textured bezel ring in the hole. That way, what you grip doesn't rotate around your thumb. It would be cool, but it's definitely not necessary.